[Closed] Building wheels with carbon rims. Any useful tips?

Lighter spokes would be my recommendation. My wheel builder built me a set of aluminium road disc wheels, used Sapim Race spokes, on my 35mm carbon 29er wheels he used lighter Laser spokes and they are very stiff.

I use a little oil on the spokes to lessen binding but other than that I find it very easy to build carbon rims. Bring the tensions up evenly like you would an alu rim and it'll be pretty true with little effort.

Measure the ERD of the rim yourself in several places.
I've built up countless Chinese carbon rims over the past few years & not all are created equal-the wall thickness can vary, resulting in uneven ERD measurements & uneven tension, so if that happens, take your time & it will always be a compromise.
If you get a good pair, then they're a doodle to build.

OK thanks. I have been looking at them wondering how round they actually are (like any rim sourced from anywhere). They certainly look very nice.

They often look & measure round until you measure the ERD & the wall thickness varies, so the amount of nipple coming through to meet the spoke also varies 2-3mm, which makes a huge difference & a real hassle building.
Also check if they're supposed to be built with nipple washers, as some are but aren't supplied.

Aluminium nipples are a waste of time as are skinny spokes like DT Revs unless you like re-tensioning them regularly. As these sound to be your first wheelbuild, then get yourself a spoke-tension meter as carbon rims aren't forgiving and getting even tension is even more critical.

Uneven wall thickness has no effect on spoke tension that can't be adjusted with a few more or less turns of the spoke key. Yeah, they might in theory be a bit weaker, but if they're massively out you should be sure a warranty replacement. Spoke length isn't necessarily as super critical as some say because they often have quite deep rim wells so you can get away with protruding spokes fairly well.

I don't know how it is for others carbons but my light bike rims rims are rated to a higher pull through force than the DT supercomps I used to build the wheels.

Despite what people seem to say on here, wheel building is not a black art. Take the time to read what you're going to do before hand, take your time and be methodical. I found having an actual wheel with me for reference the first time pretty handy.

The only thing about carbons that surprised me was that, compared to ALU rims, they needed higher spoke tensions. If this is your first build, going that high straight away might make you a bit nervous.

I took the tensions up from ALU levels incrementally with rides in between, until I found the point that they were no longer unwinding.

Aluminium nipples are a waste of time as are skinny spokes like DT Revs unless you like re-tensioning them regularly.

Rubbish. Alu nips aren't worth the hassle except on a light build, but nowt wrong with Revs et al. They can wind up a bit when building, but if you build them properly there's no reason they'll need retensioning.

Yup, my revs need no more attention than my comps. Alu nipples can **** off though.

Maybe this is cowardly but expensive rims wouldn't be my choice for a first foray in wheelbuilding. I'd want everything to be as good as it could be; I'm a handy guy so I'm confident I could build a usable wheel with a bit of investment of time... But it's really not expensive to get a pro to do a first class job, even if you consider your own time as free.

Mind you, half the point of doing your own spannering is because you like it.

Id definitely practice with an old wheel first!

I'm certainly no wheel building expert. Done it a couple of times; struggled a bit getting it straight at the end. Mostly with uppy downy wobble.

I guess due to carbon rims being much stiffer; they wont show up imperfections in the build as easy? So you could have wonky spoke tension, but the rim is holding it so it looks straight.

I may be wrong?

It takes less skill to get a true wheel with a carbon rim due to them being stiffer. However, if you know you can balance the tension, it does make the build easier. As above though, it also makes it easier to get wrong.

Interestingly, I've been finding that spoke tension drops on my lb rims when tyres are fitted. I build a little tighter to compensate for this and may even consider nipple washers on the next build to help with that.

Interestingly, I've been finding that spoke tension drops on my lb rims when tyres are fitted. I build a little tighter to compensate for this and may even consider nipple washers on the next build to help with that.

It happens on almost every wheel build IMO. more so with tubeless for some reason.

It's the tighter bead on tubeless tyres that lowers the tension once they're seated. It's much more pronounced with road tubeless.

My last set of wheels I built up myself then got the local LBS to tension/true up. Saved me over 50% of the price to build from scratch and was interesting leaning how to lace the rims up.
Will be doing the same for my new wheels.

Interestingly, I've been finding that spoke tension drops on my lb rims when tyres are fitted. I build a little tighter to compensate for this and may even consider nipple washers on the next build to help with that.

I experienced this to the extreme that I'd built a pair of wheels nice and tight, put some tyres on tubeless, pumped to about 40psi to make sure they'd seated properly, then came back to it the next day and most of the spokes were floppy! Had to put a couple of turns on all the nipples with the tyre on!

With the tyre off, the spoke tensions were now crazy high and I was worried the nipples might just pull straight through the rim!

My current wheels where my first go at wheel building.

I used a torque screw driver I had laying around (1 to 5Nm I think it adjusts to) to tighten the spoke nipples evenly.

Slowly increased the setting on the screw driver until the spokes felt about the same tension as a factory built wheel from another bike.

Then I put the wheels in the frame/forks and used zipties on the seat stay bridge and fork bridge as a guide to true and dish the wheels. I used a spoke key for this bit.

They are still going strong 5 years later. 🙂

I helped my brother build a wheel too, and used a spoke key and went on feel only. Just keep working your way around hitting ever spoke and slowly increase the pressure you apply.

I'd have thought that carbon is much easier as its a much stiffer rim than alu, so should hold true during the build. You'll just have dish to deal with at the end.

Aluminium nipples are a waste of time as are skinny spokes like DT Revs unless you like re-tensioning them regularly. As these sound to be your first wheelbuild, then get yourself a spoke-tension meter as carbon rims aren't forgiving and getting even tension is even more critical.

+1 for this being rubbish, apart form alu nipples being rubbish.

Light spokes are a pain to build with as they'd rather wind up than thread into the nipples, but done right they're fine. I used some R&R supercoat grease on the threads.

Lots of useful things here guys thanks. Some things I hadn't considered or read about.

I don't know if they require nipple washers, could I use them anyway just in case? My main concern with the build is the nipples pulling through the rim. I do like to have a go at things with my bikes because it's fun and I normally know when to bail out and get a pro if it all starts going awry. I'll build the wheels and maybe get a wheel builder to finish the job we'll see.